[PATCH v3] PCI/VGA: Select SCREEN_INFO on X86

["Mario Limonciello (AMD)" <superm1@kernel.org>]

commit 337bf13aa9dda ("PCI/VGA: Replace vga_is_firmware_default() with
a screen info check") introduced an implicit dependency upon SCREEN_INFO
by removing the open coded implementation.

If a user didn't have CONFIG_SCREEN_INFO set vga_is_firmware_default()
would now return false.  SCREEN_INFO is only used on X86 so add add a
conditional select for SCREEN_INFO to ensure that the VGA arbiter works
as intended.

Reported-by: Eric Biggers <ebiggers@kernel.org>
Closes: https://lore.kernel.org/linux-pci/20251012182302.GA3412@sol/
Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 337bf13aa9dda ("PCI/VGA: Replace vga_is_firmware_default() with a screen info check")
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
---
 drivers/pci/Kconfig  | 1 +
 drivers/pci/vgaarb.c | 6 ++----
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 7065a8e5f9b14..f94f5d384362e 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -306,6 +306,7 @@ config VGA_ARB
 	bool "VGA Arbitration" if EXPERT
 	default y
 	depends on (PCI && !S390)
+	select SCREEN_INFO if X86
 	help
 	  Some "legacy" VGA devices implemented on PCI typically have the same
 	  hard-decoded addresses as they did on ISA. When multiple PCI devices
diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c
index b58f94ee48916..436fa7f4c3873 100644
--- a/drivers/pci/vgaarb.c
+++ b/drivers/pci/vgaarb.c
@@ -556,10 +556,8 @@ EXPORT_SYMBOL(vga_put);
 
 static bool vga_is_firmware_default(struct pci_dev *pdev)
 {
-#ifdef CONFIG_SCREEN_INFO
-	struct screen_info *si = &screen_info;
-
-	return pdev == screen_info_pci_dev(si);
+#if defined CONFIG_X86
+	return pdev == screen_info_pci_dev(&screen_info);
 #else
 	return false;
 #endif
-- 
2.43.0